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741.
Résumé Changement de la composition des pigments biliaires de la bile de rat après obstruction. L'obstruction des voies biliaires chez le rat Wistar mène à la formation de pigments biliaires donnant par diazo-réaction des azopigments (jusqu'à 35% de la couleur totale) qui diffèrent de l'azobilirubine et de l'azobilirubin--d-monoglucuronide.

Research fellow of the Nationaal Fonds voor Wetenschappelijk Onderzoek, Belgium.  相似文献   
742.
Résumé Exposé d'une méthode permettant de faire des répliques au carbone de petits organismes tel que les aphides. L'utilisation d'un substrat de technovit® pour fixer les organismes est la partie importante de cette méthode. Le technovit a la propriété de coller la pellicule de carbonne; ainsi lorsque l'on détache celle-ci à l'aide de collodion, on obtient seulement la réplique se trouvant sur l'organisme.  相似文献   
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Zusammenfassung Nachweis, dass bei adulten, reifen Fröschen Thyroxin und Triiodothyronin die mitotische Aktivität und die DNS-Synthese in verschiedenen Organen (Augenlinse, mit Epithel, Niere Darm, Leber, Milz, Haut, Horn-und Nickhaut) zu stimulieren vermag.

This work was supported by USPHS Grant No. EY 00281-09 from the National Eye Institute, and Fight for Sight Grant-in-Aid No. G-496.  相似文献   
745.
J C Sealy  N J van der Merwe 《Nature》1985,315(6015):138-140
Models of seasonal mobility to exploit seasonally abundant food sources have been proposed for prehistoric hunter-gatherers in many parts of the world. Some such hypotheses involve fundamental and insufficiently tested assumptions about the nature of both hunter-gatherer societies and the archaeological evidence that they leave. The present study is an independent test of such a hypothesis proposed for the southwestern Cape of South Africa. In this strongly ecologically differentiated area there are four distinct ecological zones that would have offered four different sets of resources to prehistoric people. Obvious modern seasonal fluctuations in these resources, plus a considerable amount of archaeological evidence, led to the suggestion that prehistoric hunter-gatherers moved in a regular seasonal cycle across the zones; this would have allowed them to make maximum use of temporarily plentiful plant and animal foods in some areas, while avoiding lean periods in others. However, as reported here, direct measurements of food intake, as reflected in the stable carbon isotope ratios of archaeological human skeletons, reveal that this was not the case. The implications of this study extend beyond the relevance to local archaeology to more general questioning of the ways in which archaeological data should be used to generate hypotheses.  相似文献   
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The glucocorticoid receptor of rat liver recognizes nucleotide sequences near the promoter of mouse mammary tumour virus (MMTV) required for hormonal induction in gene transfer experiments. Similar nucleotide sequences have been found in the human metallothionein gene IIA and in the chicken lysozyme gene, the later induced also by oestrogen, progesterone and androgens. In microinjection experiments, deletion of only 44 base pairs (bp) of the lysozyme promoter (from -208 to -164) results in coordinated loss of progesterone and glucocorticoid-dependent gene expression. We show here that purified glucocorticoid receptor from rat liver and progesterone receptor from rabbit uterus yield similar or overlapping exonuclease III footprints in the promoter regions of MMTV and chicken lysozyme. Thus, the regulatory elements for different steroid hormones may be similar or at least share structural features.  相似文献   
749.
When charting the structure of the social behavior of autistic children by means of an ethologically analyzed playroom session, deficits appeared in the reciprocity of eye-contact and in the location of verbal initiatives. These deficits in social behavior were beneficially influenced by treatment with the adrenocorticotrophic hormone (4-9) analog ORG 2766.  相似文献   
750.
A previously reported effect of mechanically agitated dilutions of antiserum raised against IgE was investigated using the loss of metachromatic staining properties of human basophil leukocytes as a model. A series of 24 blind experiments was performed in which we determined the number of toluidine blue-stainable basophils after incubating with vortexed or non-vortexed dilutions of anti-IgE. Tenfold serial dilutions were used, in the range 10(21) to 10(30) (6.6 x 10(-26) to 6.6 x 10(-35) M anti-IgE). We found no evidence for a different effect of strongly agitated dilutions, compared to dilutions made with minimal physical agitation. In fact, in our hands no effect of extreme dilutions was shown at all. We conclude that the effect of extreme dilutions of anti-IgE, reported by Davenas et al., needs further clarification and that in this process the reproducibility of results between experimenters should be carefully determined.  相似文献   
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